Broaching-machine attachment for broaching the teeth of large internal gears.



M. J. ACTON.

BROACHING MACHINE ATTACHMENT FOR BHOACHING THE TEETH 0F LARGE INTERNAL GEARS. APPLICATION FILED MAY 2, 1918.

1 ,300,092. Patented Apr. 8, 1919.

2 SHEETS-SHEET I.

M. J. ACTON. BROACHING MACHINE ATTACHMENT FOR BROACH'ING THE TEETH 0F LARGE INTERNAL GEARS.

APPEICATION FILED MAY 2, 191a. Patented Apr 8,1919.

2 SHEETSSHEET 2.

UNITED STATES PATENT ornroE.

MICHAEL J. ACTON, OF FRAMINGHA M, MASSACHUSETTS,-ASSIGNOR TO LAPOINTE MACHINE TOOL COMPANY, OF HUDSON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

BROACHING-MACHINE ATTACHMENT FOR BBOACHING THE TEETH OE LARGE INTERNAL GEARS.

Specification of Letters Patent.

Patented Apr. 8, 1919.

To all whom it may concern:

Be it known that I, MICHAEL J. ACTON, a

citizen of the United States, residing at Framingham, in the county of Middlesex and State,0f Massachusetts, have invented.

a new and useful Broaching-Machine Attachment for Broaching the Teeth of Large Internal Gears, of'which the following is a specification.

The object of this invention is to provide an attachment for an ordinary or approved broaching machine by which the teeth of large internal tools. z

The invention is illustrated in the accompanying two sheets of drawings, in which- Figure '1 is an end elevation of the attachment;

Fig. 2 is a cross sectional elevation;

Fig. 3 is a cross sectional elevation of the base plate or supporting ring;

Fig. 4 is a cross sectional elevation of the revolving gear support; 7

Fig. 5 is a cross sectional elevation of the cutting tool support;

Fig. 6 is a partial sectional view of the gear blanks and spacing ring;

Fig. 7 is 'a partial sectional elevation of the face plate;

Fig. 8 is a side elevation of the cutter bar;

Fig. 9 is a cross sectional elevation of one form of cutter bar;

Fig. 10 is a cross sectional elevation of another form of cutter bar, and

Fig. 11 is a partial view of the work when completed.

Referring to the drawings and in detail, 10 designates a supporting base or cylinder .which is provided with a slotted member 11.

The member 11 is shaped to engage into the hole in the face plate of-the broaching machine, and the supporting piece is fastened thereto by screws 12. The broaching machine may be of any common or approved form, such as that shown in my companion application filed oneven date herewith, Se

I rial No. 232,128.

14 which has a number of positioning.

gears can be cut by breaching.

notches 15 out therein. The supporting base 10-is provided with ears 16 between which a latching finger 17 is pivoted on a pin 18, sald supporting base being also provided with additional ears 19 for holding the latching piece accurately in position. By raising the latching piece the blank'support 13 can be turned and the latching piece then reset.

A face or clamping plate -20 is secured on the outer face of the blank support 13 by screws 21 which pass through holes or slots 22 in the face plate, each slot having an enlarged end portion. The face plate can thus e removed b loosening the screws 21 and turning the ace plate so that the large end portions of the slots will come under the heads of the screws.

The gear blanks which are to be out are designated'by 23--23, two of which blanks may be opposed and may be held apart by a spacing ring 24 if desired. Teeth 25 are to be cut on the inside of the blanks 23-23. The blanks are held in position by being placed within the blank support 13 and by securing and tightening the face plate 20 in position. A cutter bar support 26 is held to the supporting base 10 by screws 27, the support having-a hub 28 fitting in a recess 29in the'supporting base 10.

The cutter bar A is made up of a series of teeth. These teeth may be separate sections of metal as illustrated in Fig. 9, or the teeth may bef'cut in one block as illustrated in Fig. 10. The teeth are carried by a supporting piece .30 which preferably extends cutter base or su port 26. A wearing block or shim 31 is pre erably arranged in the bottom of the cutter base to take the wear of the base piece 30.

In operation the blanks are placed in the blank support 13 o posed to each other, and the support place in the supporting base 10, as shown in Fig.2. The face plate is then clamped in position. The machine is then started and the cutter bar is drawn through the blanks to the left as illustrated bar is then returned to original position, the latching piece raised and the blank support given a turn until the latching piece engages the next notch. The operation is then repeated and continues until all the Having thus described'my invention, what I claim and desire to secure by Letters Patent is- 1. A broaching machine attachment comrising a base plate or supporting ring havmg a substantially cylindrical recess therein, a blank support revolubly fitted therein, means to hold an annular blank in said support, and a fixed support for the cutting a tool.

2. A broaching machine attachment comprising a base .plate, a blank support revolubly fitted therein, a cutting tool support secured to the base plate, and a face or clamping plate detachably secured to the blank support.

3. A broaching machine attachment comprising a base plate, a blank support revolubly fitted therein, a cutting tool support secured to the base plate, and a face or clamping plate detachably secured to the blank support by slot and screw connections.

4. A broaching machine attachment comprising a base plate or supporting ring, a blank support revolubly fitted therein, a cutting tool support secured to the base plate, a face or clamping plate detachably secured to the blank support, and a cutter bar comprising a number of toothed rods arranged in a supporting piece fitted in the cutting tool support.

5. A broaching machine attachment comprising a base plate or supporting ring, a

ank support revolubly fitted therein and effective to accurately position two annular blanks and an interposed spacing ring, a latching mechanism for holding the blank support in different positions, a cutting tool support secured to the base plate, a face or clamping plate detachably secured to the blank support to retain said blanks and spacing ring therein, and a cutting tool fitted to slide in the cutting tool support.

In testimony whereof I have hereunto afiixed my signature.

MICHAEL J. ACTON. 

